I read NetBeans Code Snippet Module
Tutorial(http://platform.netbeans.org/tutorials/nbm-palette-api1.html) again.
And I found three point.

1. Declaring the Resources
This section's first description described as below.
Select XML Document in the XML folder and click Next. Type BR in Class Name.
However, "Type BR in Class Name" should be chage to "Type BR in File Name". 
 And next sentence of above line described as below.
Type \resources at the end of src\org\netbeans\modules\newhtmlsnippets.
However, this sentence doesn't indicate where to type this word. So you 
should change like this.
Type \resources at the end of src\org\netbeans\modules\newhtmlsnippets in Folder.

2. Registering the Resources
First step is add the following tags to the layer.xml file. Actually we have to
wirte this code between <filesystem> and </filesystem>. However this description
doesn't describe this.

3. Using the Module
In the section of "Using the Module" you put screen shot. But this screen shot
is  unnatural and wrong. Because we define "New Line" between "Table" and
"Ordered List", therefore "New Line" should display after the "Table".